Go to Top

Limiting data loss from data stores: Virtualisation vs Physical Harware RAIDs

Virtual Storage

The advent of virtualisation in the IT industry has brought about many drastic changes in the way that corporate data is stored: administrators everywhere are looking at this technology in order to consolidate old hardware and to find a streamlined solution for their storage needs.

The big question from a data recovery point of view is: which is safer, data stored in a virtualised environment or data stored directly on a physical RAID?

This question is rather complex to answer, but there is one very important thing to remember; whether you are using virtualisation or not, ultimately you are still relying on physical hardware to store your data. The key difference when looking at virtualisation, is how you manage that hardware in order to limit the chance of data loss.

If we look at a simplified setup for a SMB and compare the two situations below:

Data Store 1: A single traditional “physical” server, built of 10 SAS drives

Data Store 2: A single physical server built of 10 SAS drives and running a virtualised environment

In addition, we can assume that both of these RAIDs are identical e.g. RAID5.

From a data recovery point of view both of these systems are equally susceptible to data loss as they are both reliant on a single physical RAID and it’s constituent drives. A better solution for both of the situations above would be to have two physical servers: one for the active data store, and the other as a backup.

A virtualised setup still needs to be built upon a foundation of physical devices, just like traditional RAIDs have always been, these could be fibre channel, SCSI, SAS or SSDs. With this in mind we can see that virtiualised environments can still be prone to physical failures. However, the important advantage is that virtualisation gives us the ability to migrate and backup data with much greater ease.

Conversely, virtualisation management tools are so easy to use that there can be an increased risk of human error. There have been many cases of users deleting virtual machines by accident, or in some cases deleting entire server’s worth or virtual machines!

The key to successful implementation of virtualisation and limiting the chance of data loss is to have key backup and recovery procedures in place, always remembering that you need to keep a careful eye on your hardware, and should that hardware fail, you may well find yourself in a potential data loss situation. Simply moving to virtualised environment is not enough to protect your data, and relying on a single physical server – whether it be running virtualisation software of not – is a risky route to take.

, , , ,

Leave a Reply